Some embodiments described herein relate generally to multipath switch fabrics, and, in particular, to methods and apparatus for implementing a handshake protocol in a link aggregation group (LAG)-based multipath switch fabric for multipath operations, administration and maintenance (OAM).
Some known switch fabrics implement a standard three-way handshake protocol to confirm bidirectional connectivity between two neighboring switches. Based on such a standard three-way handshake protocol, an upstream switch establishes bidirectional communication with a downstream neighboring switch by exchanging three regular messages on the connecting link between the two switches. In a LAG-based multipath switch fabric, an upstream switch is typically connected to multiple downstream neighboring switches, and a message is sent from the upstream switch to a downstream neighboring switch based on, for example, a LAG hashing mechanism. As a result, a regular message is typically not deterministically sent to a given downstream switch. Thus, the standard three-way handshake protocol cannot be implemented for two neighboring switches in the LAG-based multipath switch fabric.
Accordingly, a need exists for a handshake protocol that can be used to confirm bidirectional connectivity of two neighboring switches in a LAG-based multipath switch fabric, thus multipath OAM can be performed for that multipath switch fabric.